Most of the studies that have examined whether cancer risk declines after a person stops drinking alcohol have focused on head and neck cancers and on esophageal cancer. In general, these studies have found that stopping alcohol consumption is not associated with immediate reductions in cancer risk; instead, it may take years for the risks of cancer to return to those of never drinkers.

For example, a pooled analysis of 13 case-control studies of cancer of the oral cavity and pharynx combined found that alcohol-associated cancer risk did not begin to decrease until at least 10 years after stopping alcohol drinking. Even 16 years after they stopped drinking alcohol, the risk of cancer was still higher for ex-drinkers than for never drinkers.

In several studies, the risk of esophageal cancer was also found to decrease slowly with increasing time since stopping alcohol drinking. A pooled analysis of five case–control studies found that the risk of esophageal cancer did not approach that of never drinkers for at least 15 years after stopping alcohol drinking.

Rehm J, Patra J, Popova S. (2007) Alcohol drinking cessation and its effect on esophageal and head and neck cancers: a pooled analysis. International Journal of Cancer ;121(5):1132-1137.

And then I went looking for more. Newer research I came across via Google Scholar was this:

For alcohol use, a beneficial effect on the risk of head and neck cancer was only observed after ≥20 years of quitting (OR 0.60, CI 0.40–0.89 compared with current drinking), reaching the level of never drinkers.

As I suspected though there is very little research into this area so far. Be interesting to revisit the question in a year or two’s time to see if more new research is being published which I suspect it will. If you find any can you forward it my way? Thanks 🙂